Pistorius was dressed up in a T-shirt and shorts unlike his previous appearances in suit and tie. The same way he was dressed on the night of shooting.

While addressing the court, he explained having a heard a noise that made him think it could be an intruder who may have climbed up his bathroom window. "That was the moment everything changed," he said. "I thought that there was a burglar that was gaining entry to my home."

Initially I just froze," he admitted, per NBC News. "The first thing that ran through my mind was that I needed to arm myself."

Because Pistorius "didn't have my legs on," he feared an intruder "could come at me at any time," he said.

The four rounds that Pistorius fired through the door, three of it hit his girlfriend Steenkamp almost instantly. He maintained that it was a case of mistaken identity.

On Monday, Pistorius broke down while apologizing to Steenkamp's family, telling her parents he was "simply trying to protect Reeva."